A large round glass-fronted silvered brass pendant reliquary is theca that houses the first-class ex ossibus (of the bone) relic of one of Saint Margaret Mary Alacoque. A significant relic arranged as a flower, affixed to a gold silk ground surrounded by gilt silver wire ornamentation and identified in Latin on a manuscript cedula S.Marguerite Marie (Saint Margaret Mary [Alacoque]). On the back, under a protective cap, the theca is secured with a seal of red Spanish wax bearing an imprint of a coat of arms of an unidentified Roman Catholic Bishop.
Saint Margaret Mary Alacoque, V.H.M. (French: Marguerite-Marie Alacoque) (†1690), was a French Roman Catholic nun and mystic, who promoted devotion to the Sacred Heart of Jesus in its modern form. Mariologists refer to Saint Marguerite Marie Alacoque as "living proof how Marian devotion is linked to 'Christology'" and the adoration of Jesus Christ. She was canonized by Pope Benedict XV in 1920, and her Feast is celebrated on October 16. She is a Holy Patron of those suffering with polio, devotees of the Sacred Heart, and for the loss of parents.